Cyclic loading response of reinforced concrete tilt-up structures with plywood diaphragms

An experimental program was developed to study, under cyclic loading, the strength and deformation capacity of tilt-up structures with plywood diaphragms. Two models of tilt-up systems were constructed and tested in the Newmark Civil Engineering Laboratory. The specimens were representative of one-story warehouse construction in the western U.S. The overall dimensions of the two test specimens were the same; however, the number and distribution of the reinforced concrete wall panels were varied. Each specimen was subjected to a series of fully reversed lateral loadings. The measured responses of the the test specimens were discussed in term of the in-plane displacements of the diaphragm, the distortions of the sub-diaphragm, the relative movements of individual plywood panels, the transverse displacements of the reinforced concrete wall panels, and the diaphragm chord forces.; An analytical model was also developed as part of this study. A procedure for modelling the lateral load response of plywood roof diaphragms was developed and verified using existing test data. That procedure was then extended to the roof diaphragms of the test specimens and combined with a second procedure developed to model the reinforced concrete wall panels. The overall model was then used to calculate the response of the test specimens.; In combination, the experimental and analytical studies demonstrated that the response of reinforced concrete tilt-up structures with plywood roof diaphragms to lateral forces is controlled primarily by the behavior of the plywood roof diaphragms. The response is controlled secondarily by the connections between longitudinal and transverse wall panels and the loads for cracking of the longitudinal wall panels.